fixed scrolling left panel

static/s2f_styles.css

@@ -98,7 +98,11 @@ section[data-testid="stSidebar"] {
 
 /* === Sidebar === */
 section[data-testid="stSidebar"] {
+    position: fixed !important;
+    top: 0 !important;
+    left: 0 !important;
     width: 360px !important;
+    height: 100vh !important;
     max-height: 100vh !important;
     overflow-x: hidden !important;
     overflow-y: auto !important;
@@ -116,6 +120,8 @@ section[data-testid="stSidebar"] {
 }
 @media (max-width: 768px) {
     section[data-testid="stSidebar"] { width: 100% !important; max-width: 100% !important; }
+    [data-testid="stAppViewContainer"],
+    .appview-container .main { margin-left: 0 !important; }
 }
 section[data-testid="stSidebar"] [data-testid="stWidgetLabel"],
 section[data-testid="stSidebar"] [data-testid="stWidgetLabel"] p {
@@ -522,6 +528,11 @@ hr { border-color: #cbd5e1 !important; opacity: 0.7; }
     text-align: center;
     line-height: 1.4;
 }
+/* Main content: offset for fixed sidebar so it doesn't overlap */
+[data-testid="stAppViewContainer"],
+.appview-container .main {
+    margin-left: 360px !important;
+}
 .block-container {
     padding-bottom: 2.5rem !important;
     max-width: 1050px !important;